March 20, 2012
The U.S. Supreme Court unanimously held today in Mayo v. Prometheus that the personalized medicine dosing process claimed in Prometheus' patents effectively describes a law of nature, and is therefore not patentable subject matter. Today's opinion invalidates the two Prometheus patents at issue, and reverses the finding of the Court of Appeals for the Federal Circuit, which in turn had reversed the District Court's initial decision that the two patents were invalid for claiming a law of nature.
Following the Supreme Court’s 2010 decision in Bilski v. Kappos, the Mayo case is important for further defining the bounds between patentable and non-patentable subject matter – namely, how far medical diagnostic companies can go in broadly claiming methods of screening, diagnosis and treatment. The Prometheus patents relate to the correlations between thiopurine metabolite levels and the toxicity and efficacy of thiopurine drugs. These correlations help doctors set drug dosages for patients with Crohn’s disease.
In its analysis, the High Court weighed whether the method claims of the Prometheus patents include enough additional limitations as to how the natural correlations are being applied, or whether they merely describe a law of nature and only add “well-understood, routine, conventional activity, previously engaged in by those in the field.” The Court found the latter.
In very general terms, what can be taken from today’s ruling is that method claims involving a natural law or phenomenon, in order to constitute patentable subject matter, must go significantly beyond stating a natural law. Such claims should include additional steps or limitations, for example, which apply a law of nature in a manner that is not just “well-understood, routine, conventional activity, previously engaged in by those in the field”.
The Court’s opinion can be obtained from: http://www.supremecourt.gov/opinions/11pdf/10-1150.pdf
